Improvement in head-blocks foe saw-mhis



y @eine tars @anni @frn IMPROVEMENT IN HEAD-BLOCKS FOR SAW-MILLS.

B. F MCKINLEY, 0F CINCINNATI, OHIO, ASSIGNOR` To 'IIIMSELF AND II. n.

'MATTHIAS OF SAME PLACE. i Letters Patent No. 60,401, dated December 11, 1866.`

TO ALL WHOM IT MAY CONCERN:

Be it` known thatlI, B. F. McKINLEY, of Cincinnati, in the county of Hamilton, and State of Ohio, have invented a new and improved Head-Block for Saw-Mills; and I do hereby declare that the following is a full, clear, and exactdescription thereof, which will enable those skilled in the art to make and use the' same, reference being had to the accompanying drawings, forming part of this specification, in which- Figure 1 is a side view of my invention.

Figure 2, a plan or top view of thesame. Similar letters of reference indicate corresponding parts.

This invention relates to a new and 'improved head-block for saw-mills, and it consists in a novel means employed for operating or moving the`r knee, whereby the log is set to the saw, as hereinafter fullyshowxr and 's'. described, and by which the log may be set with accuracy and so as to cause the log to be sawed into boards or planks of varying thicknesses, as may be required.

A representsV the body of the head-block, on which the log to be sawed (shown in red) rests, and Bis a slide, which is fitted and rests upon, A, and has an upright `baroi knee C, at one end of it, and a cam D at the oppo site end, said cam,having an arm E connected toit, with a weight F at its outer end, as shown clearly in iig. 1. The slide B, has aA horizontal bar G, connected to one side of it, said bar being at one side'of the body A, of the head-block, and having a rack a, at its inner side. H H are spring or elastic pawls, which Vengage with the rack a, wheny the device is at work. These pawls are attached' to a slide, I, which is iitted and works between suitable guides at the sidof the body, A, opposite to the side where the bar G works. The slide I is operated by a toggle J, and a lever, K, oneof the arms b, of the toggle, being attached to the body A, of the headblock, and the other c, connected-to the slide, I. The arm c, is considerably longerthan the arm I, and has its y outer end pivoted to a horizontal bar, L, which works in suitable guides, the lever, K, being connectedto said i bar, L, by a link, M, which is attached to thel bar, L, 'by an adjustable head', N, as shown clearly in fig. 2.

The pawls HH, work through an opening d, in the body A, of the head-block, and jkeep `engaged with the k rack a, of the bar G, by-virtue oftheir own elasticity. The pawls are thrown out from the rack a when required,

by means of an eccentric, O, having a lever, P, attached. `From the above description, it will be seen that the slide B, and knee C, will be moved in the direction4 indicated by arrow 1, each time the lever K, is moved in the direction indicated by arrow 2, and it will further be seen that the movement of the slide B and knee C, is arbitary oriixed, as the lever K, has but a certain sweep and cannot operatefbeyond .the point, 'which'brings the pivot that connects the link M, with the lever vK, in line with the -fulcrum of said lever, and the pivot which `connects the outer end of the link M, with the head N. ,The movement of the slide B and knee C, however, may be varied according'to the required thickness of `the stutfto be sawed, by adjusting' the head N, on the bar, L. `The cam D, when the arm E, is thrown over backward, prevents a retrograde movement of theslide, B, and when the slide B and knee C, have reached the extent of their forward movement on A, the arm E is thrown forward, and the .eccentric O, turned to throw the pawls H H out of gear from the rack, a, the slide B may then be readily shoved back. The device is extremely'simple and efficient, and contains. no parts liable to become deranged by use or to get out of repair. An equivalent of adjustable head, may be, attaching'the link M, I to bar, L, by ya. pin passing through link M, and holes in bar, L, so graduated as to correspond to diiercnt thicknesses of lumber. iw* Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is -f The regulating of ,the movement of the slide B, and knee C, by means ofthe adjustable head N or its equivalent 0n bar L, substantially as and for the purpose speciied. v

I further claim, so adjusting head N or its equivalent on bar L, as to bring the pivot centres of link, M, and the falcrum oi' lever K, all in line when starting in combination with a similar arrangement of levers or links on headblock A, the centers of which are brought in line in stopping,iand the slide I, pawls H H, and

rack-bar Gr, all arranged substantially as and for the purpose set forth. i

v f B. F. McKINLEY.

' Witnesses: JosnrnV SOLLENBERGER,

GEO. B. GRoNFnLDnn. 

